In the proposed research, the influence of the type of fatty acid incorporated into tissue lipids on the enzymatic functions of membrane bound enzymes will be continued. Male rats kept on diets which contain trans fatty acids or erucic acid will serve as a source of tissue. The oxidation rates of acylcarnitine by the isolated mitochondria from the heart and liver tissue will be determined by measuring the rate of oxygen consumption in an oxygraph with a Clark electrode. Heart and liver mitochondria will be incubated in vitro with synthesized oleyl, erucyl or elaidyl carnitine and the rate of oxygen composition in the presence or absence of ADP will be measured and the rate of oxygen uptake and ADP/O ratio determined. An attempt will be made to correlate the respiratory activity of the mitochondria and triglyceride lipase activity with the fat accumulation that has been noted in the hearts of rats fed a source of erucic or trans fatty acids.